In many areas of fabrication, such as, for example, the construction of buildings, the technique employed is to utilize panels of a standardized size in the assembly or fabrication of the item. In the construction industry panels of sheetrock, plywood, wood paneling, plaster board, etc. are used extensively. When such panels are employed, it is necessary to locate the portions thereof which must be cut away in order to provide openings through the panel as required for junction boxes, electrical outlets, windows, doors, plumbing fixtures, etc. Traditionally, it has been necessary for the worker in the industry to take a multiplicity of measurements, both vertically and horizontally, in order to define the location of such a common item as an electrical outlet box. Additionally, the dimensions of the item requiring the cut in the panel must also be determined. These measurements must then be transposed onto the paneling material. While this has not been an impossible task, it is extremely time consumming and, as the degree of accuracy or precision in locating these cuts increases, so also does the amount of time required. Further, it is necessary to determine the area of a panel which will overlie the studding to which the panel is to be nailed.